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CVE-2026-93174

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: bpf: Copy per-CPU map value padding in copy_map_value_long() In kernel, per-CPU map elements are stored with round_up(map->value_size, 8) bytes. On UAPI lookup paths, it copies the rounded size for each CPU into a temporary buffer. However, copy_map_value_long() passes 'map->value_size' to bpf_obj_memcpy(). When the map has special fields, bpf_obj_memcpy() copies around those fields with memcpy(), and does not copy the tail padding between 'map->value_size' and round_up(map->value_size, 8). The temporary UAPI lookup buffers are allocated without __GFP_ZERO. As a result, when the per-CPU map's value size is not equal to round_up(map->value_size, 8), UAPI LOOKUP_ELEM and its variants can return stale heap contents from that padding to user space. The same issue applies to bpf_iter for per-CPU maps. Pass round_up(map->value_size, 8) to bpf_obj_memcpy() from copy_map_value_long(), so per-CPU maps both with and without special fields copy the entire per-CPU slot. Remove the now redundant round_up() from bpf_obj_memcpy()'s long_memcpy path.

Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-17 17:18:13.167000
Last modified
2026-10-30 13:20:59.020000
View original CVE JSON
{
  "id": "CVE-2026-93174",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-17T17:18:13.167",
  "lastModified": "2026-10-30T13:20:59.020",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Copy per-CPU map value padding in copy_map_value_long()\n\nIn kernel, per-CPU map elements are stored with\nround_up(map->value_size, 8) bytes. On UAPI lookup paths, it copies the\nrounded size for each CPU into a temporary buffer.\n\nHowever, copy_map_value_long() passes 'map->value_size' to\nbpf_obj_memcpy(). When the map has special fields, bpf_obj_memcpy() copies\naround those fields with memcpy(), and does not copy the tail padding\nbetween 'map->value_size' and round_up(map->value_size, 8).\n\nThe temporary UAPI lookup buffers are allocated without __GFP_ZERO. As a\nresult, when the per-CPU map's value size is not equal to\nround_up(map->value_size, 8), UAPI LOOKUP_ELEM and its variants can return\nstale heap contents from that padding to user space. The same issue\napplies to bpf_iter for per-CPU maps.\n\nPass round_up(map->value_size, 8) to bpf_obj_memcpy() from\ncopy_map_value_long(), so per-CPU maps both with and without special\nfields copy the entire per-CPU slot. Remove the now redundant round_up()\nfrom bpf_obj_memcpy()'s long_memcpy path."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "include/linux/bpf.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "448325199f574d33824dbf9121efb03558412966",
              "lessThan": "e0653c8f718109d140e806daac166c43e2b2b8bd",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "448325199f574d33824dbf9121efb03558412966",
              "lessThan": "953e85da53541a8dc3e7ad4e8532f29a34a32eae",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "448325199f574d33824dbf9121efb03558412966",
              "lessThan": "003bf840ed3326bd01396ce7d5b431cef0d371e7",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "448325199f574d33824dbf9121efb03558412966",
              "lessThan": "5e9f69829835521aa2942d1d14bd0990fbc6991e",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "448325199f574d33824dbf9121efb03558412966",
              "lessThan": "ff3f22ed8d2f350b4c24ee26e33daea5f08d58ef",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "448325199f574d33824dbf9121efb03558412966",
              "lessThan": "7cf9cd98cf6f0df3befc167ca6b54c07014d71de",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "include/linux/bpf.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.1",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.1",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.191",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.157",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.110",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.52",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.6",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/003bf840ed3326bd01396ce7d5b431cef0d371e7",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/5e9f69829835521aa2942d1d14bd0990fbc6991e",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/7cf9cd98cf6f0df3befc167ca6b54c07014d71de",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/953e85da53541a8dc3e7ad4e8532f29a34a32eae",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e0653c8f718109d140e806daac166c43e2b2b8bd",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ff3f22ed8d2f350b4c24ee26e33daea5f08d58ef",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}